This invention relates to a method of installing the rails in an elevator shaft wherein the machine and the dead end hitch are mounted on the rails.
Elevator shafts are typically equipped with a number of rails to guide the components within the hoistway. In particular, one side of the elevator hoistway includes two spaced rails which together guide a counterweight. A cab rail is mounted inward of these two rails. A second cab rail is positioned on an opposed side of the hoistway. The two cab rails guide the cab within the hoistway.
Historically, a machine for moving the cab has been mounted in a machine room above the hoistway. A second component known as a dead end hitch provides a connection point for the cables or ropes which move the elevator. Typically, the dead end hitch has also been mounted in the machine room.
To mount elevator rails within the hoistway in the prior art, the rails are initially positioned within the hoistway. The machine is then used to drive a cab upwardly within the hoistway. As the cab is moved upwardly, brackets are placed at appropriate vertically spaced locations in the hoistway to guide and support each of the rails. On the side of the hoistway which includes the counterweight rails and one cab rail, a generally U-shaped bracket supports the three rails. On the opposed side, a simple clip bracket supports the other cab rail. The brackets are not fixed to the rails, but rather provide support. The walls of the building move relative to the rails as the building expands or contracts. Thus, the brackets are fixed to the walls of the hoistway, but merely guide the rails and are not typically fixed to the rails.
More recently, elevators have been designed wherein the machine and the dead-end hitch are fixed at the top of the rails. In this way, a more compact elevator assembly is provided since space above the hoistway is not required for the machine room. One complication with such an arrangement involves installing the rails. The machine will transfer the cab weight into the rails as the cab is moved upwardly within the hoistway. Until the rails are supported, they should not be called upon to bear the weight of the cab. Thus, complicated systems requiring additional means for moving the cab within the hoistway and mounting the brackets have been required when the machine and dead end hitch have been mounted to the rails.
It would be preferable to simplify the mounting of the rails into a hoistway in the type of elevator wherein the machine and/or the dead end hitch is mounted onto the rails themselves.
In a disclosed embodiment of this invention, a rail sub-assembly is mounted into one, and preferably both sides, of a hoistway. One rail sub-assembly includes the machine which is preferably mounted on the rails. A second sub-assembly includes a dead end hitch, also mounted onto the rails. The uppermost bracket is preferably fixed to the wall of the hoistway, and is also fixed to at least the cab rail. The cab is then moved vertically within the hoistway and the other brackets are mounted to the wall and to support the rails. Once the brackets are all in place, the rails are adequately supported. At that point, the connection of the upper bracket to the rail is removed. The rails are now all supported and can bear the cab weight. The present invention preferably uses the uppermost bracket; however, a bracket slightly lower may also be utilized. By fixing the bracket to the rail, the forces is transmitted through the bracket and into the wall, rather than into the unsupported rails. The ability of the building to expand or contract relative to the rail does not complicate this invention in that the connection is temporary.
In preferred embodiments of this invention, the bracket on the side having the counterweight rails is generally U-shaped, and has a central web extending between two spaced legs. A bolt extends through that central web into a cab rail. On the opposed side, a clip-like bracket is secured to the wall, and then bolted on a side of the rail. Again, each of these bolts are removed once the other brackets are in place.